1. Wash, peel and rewash the potatoes and cut them into an even size.
2. Place a saucepan of water on to boil, add a little salt and the potatoes.
3. Turn down the heat and simmer the potatoes until cooked.
4. Test them by pushing a pointed knife or skewer into the potatoes and see if the point goes easily into the middle of a potato which means they are cooked.
5. Depending on the size and type of potato used, this will take approximately 20 minutes.
6. Remove from the heat and drain the potatoes into a colander and allow them to drain well.
7. Return the potatoes to the saucepan, cover with a lid and return to the heat for a few moments so that the potatoes dry well.
8. Place the cream or milk into a small saucepan, add the butter and heat gently until the butter has melted.
9. Take the potatoes off the heat and using a masher, mash the potatoes into a smooth, lump-free mixture.
10. Add the cream and butter and mix well.